1. Field of the Invention
This invention relates to devices and methods for monitoring power sources for specified conditions and automatically alerting a host of the condition.
2. Description of the Art
A need for a practical system for reporting status in an electric utility's service area has been recognized for some time, and various systems have been proposed for using the public telephone network for providing information to a central location. U.S. Pat. No. 3,098,123 suggested installing a mechanical auto-dialer in an electrical substation which called a control room and replayed pre-recorded verbal statements. More recently, U.S. Pat. No. 4,086,434 proposed automatic meter reading equipment using a microcontroller that has ancillary alarm reporting features.
Despite these efforts, no power monitoring apparatus has been put into widespread use that is economical enough to be installed throughout the lowest levels of the power distribution network (e.g. at the 117 VAC end-user locations, as opposed to substations) and that provides sufficient information to assist a utility in determining the extent of power distribution problems. Most electric utilities still rely on customers' telephone calls when power fails.